title: Raman spectroscopic investigation on TiO2-N719 dye interfaces using Ag@TiO2 nanoparticles and potential correlation strategies.
abstract: Herein, we employ Ag@TiO2 core-shell nanoparticles for surface-enhanced Raman scattering (SERS) investigations of TiO2-N719 dye interfaces. In situ electrochemical SERS investigations of the Ag@TiO2-N719 interaction are systematically carried out under a series of electrode-potential controls. By comparing the potential dependence of resonant and pre-resonant SERS spectra recorded with different laser excitations, bidentate carboxylate linkage is considered to be involved in N719 adsorption on TiO2. Meanwhile, SCN ligand shows obvious interactions with TiO2, and their role in the adsorption and orientation of N719 on TiO2 should not be underestimated. The in situ SERS spectra of Ag@TiO2 show a clear bell-shaped intensity-potential relation for the major bands of N719. A molecule-to-TiO2 charge-transfer resonance is tentatively attributed to account for such a phenomenon. Under the influence of such a charge-transfer resonance, valuable information about the N719-TiO2 interaction as well as the intramolecular deformation of N719 is obtained.
authors.affiliation: State Key Laboratory of Physical Chemistry of Solid Surfaces and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Qiu
authors.forename: Meng
authors.initials: M
authors.lastname: Zhang
authors.forename: De-Yin
authors.initials: DY
authors.lastname: Wu
authors.forename: Song-Yuan
authors.initials: SY
authors.lastname: Ding
authors.forename: Qi-Qi
authors.initials: QQ
authors.lastname: Zuo
authors.forename: Yi-Fan
authors.initials: YF
authors.lastname: Huang
authors.forename: Wei
authors.initials: W
authors.lastname: Shen
authors.forename: Xiao-Dong
authors.initials: XD
authors.lastname: Lin
authors.forename: Zhong-Qun
authors.initials: ZQ
authors.lastname: Tian
authors.forename: Bing-Wei
authors.initials: BW
authors.lastname: Mao
mesh_terms: D004396:Coloring Agents / Q000737:chemistry*; D008024:Ligands; D053758:Nanoparticles / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry*; D010316:Particle Size; D012834:Silver / Q000737:chemistry*; D013059:Spectrum Analysis, Raman; D013499:Surface Properties; D013861:Thiocyanates / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*
chemical_list: D004396:Coloring Agents; D008024:Ligands; D009942:Organometallic Compounds; D013861:Thiocyanates; C506095:bis(2,2'-bipyridyl-4,4'-dicarboxylate)ruthenium(II) bis(tetrabutylammonium) bis(thiocyanate); C009495:titanium dioxide; D012834:Silver; D014025:Titanium
keywords: Raman spectroscopy; charge transfer; core-shell nanoparticles; dye-sensitized solar cells; titanium dioxide